How can i store array value in api post method react

Hi,

I want to store this array  in sql.in name column all name data will be store.in age and gender also like this.

this.state = {

            rows: [],

      Name: [],

      Age: [],

      Gender: [],

}

1. 0: {key: 0, name: 'x', age: 24, gender: 'F'}
2. 1: {key: 1, name: 'x', age: 23, gender: 'F'}
3. 2: {key: 2, name: 'x', age: 26, gender: 'F'}

        handleSubmit = async event => {

   
    console.log("submitting: ", this.state.rows);
    let arr = this.state.Name;

   let arr2 = this.state.Age;

 let arr3 = this.state.Gender;

    this.state.rows.forEach((i, v) => {
        arr.push(i.name);
      });
      this.state.rows.forEach((i, v) => {
        arr2.push(i.age);
      });
      this.state.rows.forEach((i, v) => {
       arr3.push(i.gender);
      });
      event.preventDefault();
      var body = {
        Name: arr ,

       Age:arr2,

       Gender:arr3
      };
    fetch(url, {
       method: 'post',
       headers: {'Content-Type':'application/json'},
       body: JSON.stringify(body)
    }); 
   
  }; 

this value coming from table data not from form. in c# i am using [FROMFORM] method.but this value passing null only.how can i store punch of table record to the sql from react table